Giffords and Kelly are on their seven-day seven-state "Rights and Responsibilities Tour," to push for expanded background checks for firearms purchases. They are also being accompanied by some families of victims of the Sandy Hook school shooting who were with them Friday evening in New Hampshire and Saturday in Maine.

This isn't the first time Giffords and Bush have met. When Giffords was recovering in a Houston hospital after she was shot in the head in a shooting at an Arizona shopping center, Bush and his wife Barbara went to visit her. In her 2011 memoir with Kelly, they write that at that point in her recovery she could only say "chicken" to the former president and first lady.

The Canadian Press, Paul Chiasson/AP Photo

Quebec Train Fire

A number of people remain unaccounted for in the town of Lac Megantic in Quebec, Canada, after an 80-tanker-long train derailed and exploded in the center of town Saturday.

At least three people were killed.

Quebec Fire Chief Denis Louzon said the center of town lay in ruins.

"Parts of buildings, trees burnt, no grass at all. Just, it's destruction," Louzon said Sunday at a news conference.

Bolivian President Evo Morales said Saturday that Snowden was welcome in his country, The Associated Press reported.

Morales said he was making the offer as a protest against the United States and European nations he accused of blocking his flight home from a Moscow summit because of suspicions that Snowden might have been aboard his plane.

Federal authorities last month filed espionage charges against Snowden, a former National Security Agency contractor accused of disclosing secret anti-terrorism programs run by the U.S. government.